var createError = require('http-errors');
var express = require('express');
var path = require('path');
var cookieParser = require('cookie-parser');
var logger = require('morgan');
var cors = require("cors");


// 引入mongoose，在app.js里面引
// mongoose就是用来连接MongoDB的
const mongoose = require('mongoose');
// 连接
// 27071是MongoDB的端口号，IT231是数据库名称
mongoose.connect('mongodb://127.0.0.1:27017/IT231', { 
    useNewUrlParser: true,
    useUnifiedTopology: true 
  }
);

// 判断是否连接成功
const db = mongoose.connection;
db.on('error', console.error.bind(console, 'connection error:'));
db.once('open', function() {
  console.log('数据库连接成功')
});


var indexRouter = require('./routes/index');
var adminRouter = require('./routes/admin');

var app = express();

app.use(cors());

// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'ejs');

app.use(logger('dev'));
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));

app.use('/api/index', indexRouter);
app.use('/api/admin', adminRouter);

// catch 404 and forward to error handler
app.use(function(req, res, next) {
  next(createError(404));
});

// error handler
app.use(function(err, req, res, next) {
  // set locals, only providing error in development
  res.locals.message = err.message;
  res.locals.error = req.app.get('env') === 'development' ? err : {};

  // render the error page
  res.status(err.status || 500);
  res.render('error');
});

module.exports = app;
